Economic theory has a serious and embarrassing problem: it does not appear to have a rigorous and well-defined concept of money. This is why orthodox textbooks, when introducing money have to resort to a descriptive sleight of hand and state that “money is what money does”. They typically go on to say that it is the unit of account, the means of exchange and a reserve of value. But they fail to add that these functions are not exclusive of money.

That money poses a serious problem for mainstream economic theory is best exemplified by the fact that the most sophisticated account of interdependent markets (general equilibrium theory) does not tolerate the introduction of money (Hahn 1982). That’s an amazing headline story, one that should be taught in Economics 101.

“For the Snark’s a peculiar creature, that won’t / Be caught in a commonplace way./ Do all that you know, and try all that you don’t: / Not a chance must be wasted today!

Lewis Carroll, The Hunting of the Snark

Of all the assumptions of general equilibrium theory, the Walrasian auctioneer may very well be the most important one. Because macroeconomics has been absorbed by neoclassical microeconomics, today the role of the auctioneer is also embedded in macro models. For example, the work of Lucas and Kydland and Prescott relies heavily on the presence of an auctioneer. It is therefore no exaggeration to say that this assumption runs through the spinal chord of orthodox economic theory, both micro and macro.

Although everyone seems to agree that this is not a good assumption, the auctioneer is also one of orthodoxy’s less well-understood figures. Both friend and foe repeatedly misunderstand its role and its intimate relation to stability theory in general equilibrium models.